Universal SFP support

Abstract

Techniques for supporting optical and electrical protocols, such as on the ports of a line card in a network device, are provided. A port on a line card supports optical and electrical connections. The PHY monitors a signal to determine if the transmission connection at the port has changed, such as from optical to electrical, or vice versa. If there has been a change, the PHY is directed to reset a port to correspond to the appropriate transmission connection. By resetting the port, the PHY changes the protocol that is utilized with the signals (e.g., NRZI or 3-Level MLT3).

1. A method of selecting optical or electrical transmissions on a port of a line card in a network device, the line card including an integrated circuit that supports optical and electrical transmissions, comprising:
 monitoring the integrated circuit to determine whether the port has a transmission connection to a transceiver module that is different than the port is configured, wherein the port comprises a single transmission connection to the transceiver module which is configured for either optical or electrical transmission; 
 determining that the port has the transmission connection that is different than the port is configured; and 
 instructing the integrated circuit to reset the port to the transmission connection at the port. 
 
     
     
       2. The method of  claim 1 , wherein a signal detect (SD) signal on a pin on the port indicates whether the transmission connection is optical or electrical. 
     
     
       3. The method of  claim 2 , wherein the integrated circuit stores in a register the values of the SD signal for each of the ports of the line card. 
     
     
       4. The method of  claim 3 , wherein the monitoring the integrated circuit comprises monitoring the register to detect changes in the register. 
     
     
       5. The method of  claim 1 , wherein the instructing the integrated circuit comprises sending an instruction to the integrated circuit to reset the port as is specified in a register. 
     
     
       6. The method of  claim 5 , further comprising modifying the register to specify the port. 
     
     
       7. The method of  claim 1 , wherein the integrated circuit is designed to configure the transmission connection of each port of the line card at powerup. 
     
     
       8. The method of  claim 1 , wherein resetting the port changes a protocol utilized with signals from the transmission connection. 
     
     
       9. The method of  claim 8 , wherein the protocol is NRZI for optical or 3-Level MLT3 for electrical. 
     
     
       10. A computer program product for selecting optical or electrical transmissions on a port of a line card in a network device, the line card including an integrated circuit that supports optical and electrical transmissions, comprising:
 computer code that configures a processor to monitor the integrated circuit to determine whether the port has a transmission connection to a transceiver module that is different than the port is configured, wherein the port comprises a single transmission connection to the transceiver module which is configured for either optical or electrical transmission; 
 computer code that determines that the port has the transmission connection that is different than the port is configured; 
 computer code that configures a processor to instruct the integrated circuit to reset the port to the transmission connection at the port; and 
 a computer readable medium that stores the computer codes. 
 
     
     
       11. An apparatus that selects optical or electrical transmissions on a port of a line card in a network device, the line card including an integrated circuit that supports optical and electrical transmissions, comprising:
 means for monitoring the integrated circuit to determine whether the port has a transmission connection to a transceiver module that is different than the port is configured, wherein the port comprises a single transmission connection to the transceiver module which is configured for either optical or electrical transmission; 
 means for determining that the port has the transmission connection that is different than the port is configured; and 
 means for instructing the integrated circuit to reset the port to the transmission connection at the port. 
 
     
     
       12. A line card for a network device that selects optical or electrical transmissions on a port of a line card in a network device, the line card including an integrated circuit that supports optical and electrical transmissions, comprising:
 computer code that configures a processor to monitor the integrated circuit to determine whether the port has a transmission connection to a transceiver module that is different than the port is configured, wherein the port comprises a single transmission connection to the transceiver module which is configured for either optical or electrical transmission; 
 computer code that determines that the port has the transmission connection that is different than the port is configured; 
 computer code that instructs the integrated circuit to reset the port to the transmission connection at the port; and 
 a computer readable medium that stores the computer codes. 
 
     
     
       13. A method of selecting optical or electrical transmissions on a port of a line card in a network device, the line card including an integrated circuit that supports optical and electrical transmissions, comprising:
 monitoring a first register of the integrated circuit to determine whether the port has a transmission connection to a transceiver module that is different than the port is configured, wherein the port comprises a single transmission connection to the transceiver module which is configured for either optical or electrical transmission; 
 determining that the port has the transmission connection that is different than the port is configured; 
 modifying a second register of the integrated circuit to specify the port that has the transmission connection that is different than the port is configured; and 
 instructing the integrated circuit to reset the port specified by the second register to the transmission connection at the port. 
 
     
     
       14. The method of  claim 13 , wherein a signal detect (SD) signal on a pin on the port indicates whether the transmission connection is optical or electrical. 
     
     
       15. The method of  claim 14 , wherein the integrated circuit stores in the first register the values of the SD signal for each of the ports of the line card. 
     
     
       16. The method of  claim 15 , wherein the monitoring the integrated circuit comprises monitoring the first register to detect changes in the first register. 
     
     
       17. The method of  claim 13 , wherein the integrated circuit is designed to configure the transmission connection of each port of the line card at powerup. 
     
     
       18. The method of  claim 13 , wherein resetting the port changes a protocol utilized with signals from the transmission connection. 
     
     
       19. The method of  claim 18 , wherein the protocol is NRZI for optical or 3-Level MLT3 for electrical. 
     
     
       20. A computer program product for selecting optical or electrical transmissions on a port of a line card in a network device, the line card including an integrated circuit that supports optical and electrical transmissions, comprising:
 computer code that configures a processor to monitor a first register of the integrated circuit to determine whether the port has a transmission connection to a transceiver module that is different than the port is configured, wherein the port comprises a single transmission connection to the transceiver module which is configured for either optical or electrical transmission; 
 computer code that determines that the port has the transmission connection that is different than the port is configured; 
 computer code that configures a processor to modify a second register of the integrated circuit to specify the port that has the transmission connection that is different than the port is configured; 
 computer code that configures a processor to instruct the integrated circuit to reset the port specified by the second register to the transmission connection at the port; and 
 a computer readable medium that stores the computer codes. 
 
     
     
       21. An apparatus that selects optical or electrical transmissions on a port of a line card in a network device, the line card including an integrated circuit that supports optical and electrical transmissions, comprising:
 means for monitoring a first register of the integrated circuit to determine whether the port has a transmission connection to a transceiver module that is different than the port is configured, wherein the port comprises a single transmission connection to the transceiver module which is configured for either optical or electrical transmission; 
 means for determining that the port has the transmission connection that is different than the port is configured; 
 means for modifying a second register of the integrated circuit to specify the port that has the transmission connection that is different than the port is configured; and 
 means for instructing the integrated circuit to reset the port specified by the second register to the transmission connection at the port. 
 
     
     
       22. A line card for a network device that selects optical or electrical transmissions on a port of a line card in a network device, the line card including an integrated circuit that supports optical and electrical transmissions, comprising:
 computer code that configures a processor to monitor a first register of the integrated circuit to determine whether the port has a transmission connection to a transceiver module that is different than the port is configured, wherein the port comprises a single transmission connection to the transceiver module which is configured for either optical or electrical transmission; 
 computer code that determines that the port has the transmission connection that is different than the port is configured; 
 computer code that configures the processor to modify a second register of the integrated circuit to specify the port that has the transmission connection that is different than the port is configured; 
 computer code that configures the processor to instruct the integrated circuit to reset the port specified by the second register to the transmission connection at the port; and 
 a computer readable medium that stores the computer codes.